The present invention relates to the field of shoe stretching lasts, i.e. devices for maintaining the shape of a shoe.
According to the conventional art, these lasts comprise a tiptoe portion and a heel portion connected to each other by spring means tending to maintain them in a spaced apart position, corresponding to a configuration of maximum length of the last. This last is introduced into a shoe by moving the tiptoe portion and the heel portion closer to each other, so as to put said spring means under tension, so that, once the last has been introduced, the spring means maintain the shoe in a stretched condition.
The main drawback of the above mentioned conventional stretching lasts lies in that the tensioning force is a function of the deformation of the above mentioned spring means, so that this force may become either too high for short shoes or too small for long shoes.